Textile machines producing cross-wound bobbins are well-known. They can be formed as spinning or winding machines. Spinning machines, for example rotor or air spinning machines, thereby produce a thread from a fiber composite. The thread produced is then wound up on a cross-wound bobbin by a winding station of the textile machine. With a winding machine, on the other hand, a thread is already present, and is rewound from a delivery coil onto a receiver coil. The receiver coil here is spooled by the winding station as a cross-wound bobbin.
Upon the operation of such a winding station, it may occur that a thread end must be found on the cross-wound bobbin. This occurs, for example, after a thread breakage or a clearer cut, that is, if a defective thread section is intentionally cut out of the thread. In such a case, the cross-wound bobbin frequently (for example, due to its inertia) cannot be stopped in time, and the thread end winds onto the cross-wound bobbin.
In order to continue the winding operation, the thread end must be found on the circumference of the cross-wound bobbin, and then connected to the subsequent thread or attached to a newly produced thread.
In many cases, the thread end is searched for with the assistance of negative pressure. Such a method and the associated device are described, for example, in European patent application EP 1 717 183 A1. There, a suction nozzle is brought into a predetermined distance from the cross-wound bobbin in two movement steps. The suction nozzle is then subjected to negative pressure and the cross-wound bobbin is rotated backwards (compared to the winding). The thread end is then sucked into the suction nozzle through a suction mouth of the suction nozzle, and is thus found.
In this example, the suction nozzle to be moved requires a high need for space. Thus, the task of the present invention is to design a thread seeking device with a lower need for space.